"If trees could scream, would we be so cavalier about cutting them down? We might, if they screamed all the time, for no good reason." -Jack Handey
I've read that in the original version of the game, one fielded all five heroes but could only have 3 on the board at a time.
Also in the original, each side had exactly one of each Hero type. You couldn’t have two Swashbucklers, for example.